Sometime typeahead stops working. I couldn't figure out what leads to this situation.
And by "not working" i don't mean you can type the first character, but afterwards whatever you type is not entered and considerd.
for example i want to search for ".themes" in my home folder and after typing . it doesn't accept more input and i can't complete search. 
another thing that i found was that if i open a new tab when i'm in this situation, typeahead works completely fine in the new tab, but going back to the previous tab i still find the typeahead non-working in that tab.
I tried to reset everything related to thunar by removing xfconf and thunar config files but that didn't seem to help.